NEW YORK -LRB- CNN -RRB- -- A rare Lincoln manuscript sold for $ 3.4 million on Thursday at Sotheby 's auction house . The 1864 letter in which Abraham Lincoln replies to the abolitionist pleas of 195 young boys and girls was bought by a private American collector over the phone .

The sale of the letter , from the Dr. Robert Small Trust , set a record for a Lincoln manuscript , a presidential manuscript and any American manuscript ever auctioned , Sotheby 's spokeswoman Susan Ollinick said .

The `` Little People 's Petition '' had asked Lincoln `` to free all the little slave children of this country . ''

Lincoln wrote , `` Please tell these little people I am very glad their young hearts are so full of just and generous sympathy and that , while I have not the power to grant all they ask , I trust they will remember that God has , and that , as it seems , He wills to do it . ''

Although Lincoln 's Emancipation Proclamation had declared freedom for all slaves held in areas `` in rebellion '' against the United States as of January 1 , 1863 , full abolition of slavery was not accomplished until adoption of the 13th Amendment to the Constitution late in 1865 .

The letter had been expected to sell for $ 3 million to $ 5 million .

About 20 Lincoln documents were among the 111 items for sale from the Small Trust .

Also included were other documents from U.S. presidents , including pages from George Washington 's diary and correspondence from Thomas Jefferson and John Adams ; a rare document signed by both Meriwether Lewis and William Clark ; about 10 documents from Robert E. Lee ; and documents from John Brown , Samuel Clemens , Orville Wright and others . E-mail to a friend

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Letter is president 's reply to children asking him to free slaves

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It was expected to sell for $ 3 million to $ 5 million

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Private American collector purchased letter over the phone